Create Cross Sections and 2D planes in Blender
depending on how sophisticated you want to go, there is a few solutions to this. If you manage to create a closed volume from your boat model (the hull I guess is the part needed), you can do it using the Boolean modifier.

Create the volume first. If your canoe is only a shell, you can use the solidify modifier to generate some thickness. if the volume is closed, you're good to go.

Create a cube and scale it so in one axis it is really flat. This will be the thickness of your section:



Add a boolean modifier, set it to 'Intersect', and choose the boat hull as the object to cut with (in the former screenshot my object is the 'Dragon'). If you now hide the boat hull, you should see the first section.



Now you only need to duplicate this object across your boat with constant offsets. Press Shift+D, X (if you want to go along the X-Axis) and then type in the amount (like 0.1) Enter. You should now have a second section in place. If that worked, hit Shift+R, which repeats your last operator (duplicate and move), and do this 10 more times to have 12 sections in the end.

These objects can be now individually selected (that's why I did not use an array modifier) and put on layers if you like. If you select one of the elements, you can see the dimensions of the bounding box (I made it visible in the screenshot) in the Transform tab:



This you can use to resize the section images later on to correct size in Photoshop or Gimp (unfortunately no way to do this out of the box afaik). Getting the images is a matter of setting up Blenders viewport and do some openGL renders. Setup a new World, make it white, and set Blenders viewport to show the world and only render:



Using the 'render OpenGL Image' button marked in the screenshot above gives you an image in the resolution set up in the render settings, so you can go for really high res templates if you need to.




For scaling the images to correct size you'll need to consult the image editors manual.